Mobile machines, in particular mobile work machines such as wheel loaders, tractors, graders, scrapers, and the like, commonly utilize operator cabs as rollover protective structures (ROPS) to protect an operator as work is being performed by the mobile machine. For example, in U.S. Pat. No. 5,636,867, McNabb et al. (McNabb) disclose a rollover protective structure and method having cross members and reinforcing members attached to four upright posts.
However, it is often desired to transport a mobile machine to a work site by carrying the mobile machine on the bed of a truck. A large mobile machine may not provide enough clearance for transport with a ROPS attached. The structure disclosed by McNabb is not designed to be readily removable and is therefore not suitable for use in transport applications.
In U.S. Pat. No. 3,976,323, issued to Godfrey, a cab mounting structure is disclosed which uses removably positionable pins to attach and remove a ROPS from a mobile work machine. However, the pins are difficult to access, the mounting hardware has numerous pieces and is complicated to assemble, and the process of installation and removal of the ROPS is therefore difficult and time consuming. In an application where quick and simple installation and removal of a ROPS is required, e.g., under adverse work conditions, a simpler and more efficient removal apparatus is required.
In U.S. Pat. No. 5,042,835, a rollover protection apparatus is disclosed by Burns which uses a roll bar assembly which may be readily moved to a desired position, then locked into place. However, situations may exist where a roll bar assembly such as disclosed by Burns is not adequate for the environment in which the operator and the mobile machine are working. For example, a mobile work machine may be used in an environment where much dust is present, thus requiring a more complete protective enclosure for an operator, such as an enclosed cab.
The present invention is directed to overcoming one or more of the problems as set forth above.